Dough sheet spreader

ABSTRACT

A dough sheet spreader through which dough is extruded in sheets of predetermined width and thickness. A multi-part housing having a downwardly distending, outwardly flaring passageway terminating in an egress, the lips of which are lined with dough release members, is adapted to receive and extrude dough-like material. Provision may be made for degassing the dough during the extrusion process. In one embodiment the thickness of the dough sheet can be varied and in another, both the width and thickness can be varied in progressive, finite steps.

This application and copending application Ser. No. 852,364 aredivisional reissue applications of U.S. Pat. No. 3,748,079. .Iaddend.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to dough sheet spreaders, particularly forthe processing of yeast dough, pizza crust, flour tortilla, noodles,macaroni and biscuits. It is also extended to means for processing thedough during extrusion to improve the texture and quality and extend theusable storage life before consumption.

Description of the Prior Art

The spreader of the present invention is adapted to be used with screwtype dough mixing and kneading machines of the type shown in U.S. Pat.No. 2,068,220 to Baechi. In that system, the screw conveyor feeds thedough through a sizing plate at right angles to the screw. Similarly,U.S. Pat. No. 2,543,198 to Plunguian et al relates to a mixing apparatushaving a cylindrical shell through which the processed material is fedby means of a helical conveyor. The material is moved into the dischargehopper which is arranged at the end of the passageway. U.S. Pat. No.2,209,824 to Louisot et al relates to a meat processing machine forshaping fat or other products into a strip of substantially uniformthickness and width. The meat is fed through a cylindrical housing forthe feed screw of an ordinary meat chopping machine which has a funnelarranged at the end. The mouth of the funnel is substantially circularin cross-section but the walls of the funnel taper to provide adischarge opening of modified oval shape. In communication with thefunnel is a passageway of upper members and lower members which togetherform a shaping passageway having an outlet opening of substantiallyrectangular cross-section. U.S. Pat. No. 3,332,369 to Freed relates to abread dough making machine having a hopper and feed screw conveyor whichfeeds into a loaf forming block through which the developed dough isextruded.

In each of these and other systems, it was not practical to producedough sheets of a width and thickness suitable for pizza crust, flourtortilla, noodles, macaroni or biscuits without further processing.Individual segments of dough could thereafter be hand stretched but thehigh labor content made the end product expensive. Alternatively,rollers could be used to further stretch the dough, but this increasedthe capital requirement for machinery, raising the expense. Often thedough stuck to the rollers, requiring expensive shut downs and/orintervention of hand operations to clear the fault. Also, with previousextrusion and spreading means, the dough would break up into lumps. Orwhere the dough jammed in the extruder, the resulting friction of theagitated dough would generate heat and cause it to cook in the spreader,mixer and kneader. Furthermore, without further processing, doughagitated and extruded by the above described means contains a great dealof occluded gases, which might detrimentally reduce the shelf life, thatis the storage time permissible before consumption, as well as result indough of inferior texture and quality.

SUMMARY OF THE INVENTION

It is the principal object of the present invention to provide animproved dough sheet spreader through which dough may be rapidly andcontinuously extruded in sheets of predetermined width and thickness,thereby eliminating intermediate hand or machine processing operationsheretofore necessary before cutting and cooking the dough in finaldimensions as required for pizza, tortilla or the like. Another objectis to provide novel means for the removal of occluded gases within thedough, thereby increasing the shelf life of the end product andproducing dough of improved texture and quality.

The above and other objects of the present invention are achieved byutilization of a dough sheet spreader of a generally triangularconfiguration, having a hollow passageway therein, through which doughis extruded. The inlet is arranged near the apex of the triangularstructure and the egress at the base. The passageway is outwardlyflaring, but narrowing in height, from inlet to egress, the lips ofwhich are lined with release material, such as Teflon to preventsticking of the dough. In operation the spreader housing distendsdownwardly from the horizontal, optimum results being achieved at anangle of approximately thirty degrees (30°) from the vertical or sixtydegrees (60°) from the horizontal. Combination means for varying doughsheet thickness, and sealing the mixing, kneading and extrusion systembetween runs may be provided. This latter feature permits rapidconversion of the spreader to differing products and also permits shutdown and start up without laborious and expensive cleaning operations,because the system is sealed to outside factors during shut down. As anadditional feature, means for removing occluded gases within the doughare provided within the spreader. In an illustrated embodiment, aspring-biased degassing plate is arranged within the spreader passagewaybetween the inlet and the egress. The degassing plate surface is intouching relationship with the flow of dough through the passageway. Thespring-biased up and down movement of the plate against the variabledensity flowing dough serves to drive out gas which was entrained duringthe mixing and kneading operations, thereby increasing the shelf life ofthe dough and improving the texture and quality. The outwardly flaring,and downwardly distending features of the present invention have beenfound to: make dough extrusion more rapid and easier; minimize, if noteliminate, the breaking of cold dough into lumps; prevent the jamming ofthe spreader with resultant agitation and cooking of the dough withinthe system; and eliminate the need for hand operations or a plurality ofroller means for processing the dough into final shapes. Instant shutdown and start up means, eliminating the need for intermediate cleaninghave also been achieved, as well as means for removing entrapped gasesin the dough and thereby improving its texture, quality and shelf life.

Another feature of the dough sheet spreader of the present inventionoffers a choice of dough sheet widths and thicknesses in a plurality ofdiscreet, progressive steps by utilization of an adjustable roller pair,each carrying a plurality of cooperating release bars at the egress ofthe spreader. Each of the rollers carries a plurality of equi-spacedbars of a release material, the bars of one roller being notched tovarious widths to receive corresponding bars of the other roller whichselectively nest to predetermined depths to form a die having an openingof desired width and height made of release material, through whichdough is extruded in a sheet of the desired dimensions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation of the improved spreader of the presentinvention;

FIG. 2 is a sectional view taken along section lines 2--2 of FIG. 1;

FIG. 3 is a front elevation of a modification of the present inventionincorporating a combination sealer and thickness control;

FIG. 4 is a sectional view taken along section lines 4--4 of FIG. 3 andadditionally illustrating the dough degassing means;

FIG. 5 is a partial exploded view showing the relationship of thedegassing plate to the spreader assembly and cover plates;

FIG. 6 is a perspective view of the overall relationship of theadjustable roller paid, each carrying a plurality of cooperating releasebars functioning as an extrusion die of variable width and thickness;

FIG. 7 illustrates the nesting of a thickness selector roller bar into awidth selector roller bar to form a die;

FIG. 8 is a front elevation of a dough spreader having said variablewidth and thickness control; and

FIG. 9 is a sectional view taken along section lines 9--9 of FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A species of the present invention arranged to process dough in sheetsof fixed thicknesses and width is shown in FIGS. 1 and 2. A spreadervessel 10 having a flange 20 is mounted at the end of a passageway 24from which dough is driven forward by screw or other means, not shown asbeing conventional in the food extruder and baking art. The spreader 10comprises a housing 14 and a cover plate 12 which generally define adownwardly distending outwardly flaring passageway 24 having an egress28, the lips of which are lined with release bars 18a, 18b, of amaterial such as Teflon. The cover plate 12 is held to the spreaderhousing 14 by securing bolts 16 and the spreader housing 14 attached tothe associated machinery by bolts 22 extending through the mountingflange 20, or some other suitable means.

In operation, the mixed dough is moved forward into the passageway 24and then downward into the spreader chamber 26. The chamber 26, being ofa generally outwardly flaring configuration, and being downwardlydistended at approximately thirty degrees (30%) from the vertical, orsixty degrees (60°) from the horizontal, may or may not be Teflon lined,and becomes more restricted as it approaches the egress 28. The doughfans out to a width and thickness as finally determined by theconfiguration of the egress 28 formed by the cover plate 12 and housing14. The lip bars 18 act in the manner of a mold release agent to affordsmooth exit of the dough from the spreader 10 onto a receiving means,such as a conveyor belt, for further processing. It has been found thatthe use of the outwardly flaring extrusion means, downwardly canted atabout thirty degrees (30°) from the vertical, or sixty degrees (60°)from the horizontal, having lip bars 18, all as shown in the presentspreader 10 has resulted in a continuous, smooth, even flow of doughwithout jamming and precooking or lumping. The operation in this mannerhas enabled spreading dough in widths and thicknesses not heretoforereadily accomplished by machine. When dough is so dimensioned to sizesutilized in special regional food specialties such as tortillas, specialhand processing is no longer required. The result is that the finalproduct can be produced in great quantities and more cheaply, withresultant benefits to the consuming public.

Dough processed by the spreader of this invention, such as tortillas, isoften stored by distribution agencies, including retailers for anindefinite time before being purchased by the ultimate consumer. It hasbeen found that if the presence of gas in the dough, entrapped duringmixing and processing, is minimized, the dough such as tortilla shellswill stay fresh longer, resulting in more efficient utilization of theproduct and greater customer satisfaction. The species shown in FIGS. 3,4 and 5 contain special features directed to the diminution of suchgases in the dough. This species also features variable means foradjusting dough sheet thickness and sealing the spreader between runs.As shown in the Figures, the spreader 30 comprises a housing 34 whichtogether with the cover plate 32 form a passageway 35, said spreaderbeing adapted to mount to conventional dough mixing and kneadingequipment by a mounting flange 36. The cover plate 32 is joined to thehousing 34 by securing means 37, such as bolts. The thickness of thedough sheet may be determined by positioning the adjustable rod assembly46 relative to the fixed rod assembly by adjustment of the handle 38which is connected to an adjustable rod holding member 48 containing anuppper lip rod 47 made of Teflon or the like, said handle 38 beingconnected to move rod 45, through an adjustable link 44 held by a setscrew 43, along its longitudinal axis thereby causing the rod holdingmember 48 to turn about its pivot point 49 by rotating pivot rod 52 inits socket 54. As shown in the Figures, the handle 38 is arranged withinthe hollow interior portion of the bushing 40, which is threadablymounted within a jam nut 41 which is itself mounted on a support bracket42 mounted on the pivot rod retaining plate 53 arranged on the spreadercover plate 32. The fixed rod assembly 50 contains a lower lip rod 51,made like the upper lip rod 47 of a release material, and their relativeposition determines the thickness of the sheets of dough. The pivot rod52 and fixed and adjustable rod assemblies 50, 46 are prevented fromlateral motion by sealing plate assemblies 84, 84a which comprise aplate at each end of Teflon 85 and steel 86 bonded together, which isheld in place by removable handles 80, 82 bearing on the sealing plateassemblies 84, 84a and threadably mounted on screws 78, 78a which extendfrom the ends of the adjustable rod assembly 46. This ability to set theupper and lower lip rods 47, 51 in an air tight relationship isextremely valuable as it obviates the necessity of completely cleaningout the system after shut down and before restarting. It greatlydiminishes the amount of time attributed to cleaning and set up, andpermits application of an optimum amount of operating time to doughproduction.

The thickness of the dough being extruded is adjusted by loosening thehandles 80, 82 and the sealing plate assemblies 84, 84a, then adjustingthe adjustable rod assembly 46 by moving the handle 38 in or out asdesired. When the desired relationship between the adjustable rodassembly 46 and the fixed rod assembly 50 is achieved, the sealing plateassemblies 84, 84a and the end handles 80, 82 are retightened.

It has been found that the texture, quality and shelf-life of the doughis improved if the gas content is reduced to a minimum. This isespecially true of the flour tortilla. While the screw action whichnormally forces dough through an extruder may accomplish a small amountof degassing, it has been found that additional means are necessary toprovide superior results. Such additional means are provided herein byan adjustably yielding degasser plate, the use of which will afford theright texture to the dough as required for high quality flour tortillas.As shown in the Figures, an adjustable degasser plate 56 is positionedto move inwardly in or out of the passageway 35 as it swings about itspivot point 74. Teflon seals 59, 59a abut the plate 56 in its withdrawnposition to prevent entrapment of the moving dough around and behind thedegasser plate 56. The plate 56 is initially placed within thepassageway 35 to the desired depth by a connecting rod member 70abutting a spring 60, the compression of which is adjusted by a screw62, all of which are arranged within the bore of a degassing platepositioning bushing 58 which is threadably mounted in the neck 66 of abushing flange 68 arranged on the surface of the spreader cover plate32. A jam nut 64 holds the positioning bushing 58 while an O-ring seal72 surrounds the connecting rod member 70 where it passes through thespreader cover plate 32, and together with the other seals serves toprevent the dough from leaking from the spreader 34. In operation, thepressure of the spring-biased degassing plate 56 in touching, tangentialrelationship to the dough as it flows through the spreader passageway 35squeezes entrained gases from the dough. The spring-biased up and downmovement of the plate 56 affords operation in spite of irregularities indough density as it flows by the plate 56. The plate 56 remains at afixed position as the dough density remains constant, but as the densityincreases, the plate 56 is pushed upward against the biasing spring 60which exerts a counter force, causing the plate 56 to press gases fromthe dough. In some instances the plate 56 can also serve the function ofpredimensioning the dough before it reaches the final extrusion dieformed by the upper lip rod 47 and the lower lip rod 51 of theadjustable rod assembly 46 and fixed rod assembly 50.

By simple modification of the dough sheet spreader of the presentinvention, particularly the egress portion, it is possible to choosedough sheet widths and thicknesses in a plurality of discreteprogressive steps. This feature is realized by utilizing at the spreaderegress, an adjustable roller pair, each carrying a plurality ofcooperating release bars. As illustrated further in FIGS. 6, 7, 8 and 9the upper, or thickness selector, roller 100 and the lower, or widthselector, roller 102, each carry a plurality of equi-spaced bars ofrelease material, the bars of the width selector roller 102 beingnotched to various widths to receive corresponding bars of the thicknessselector roller 100 which selectively nest to predetermined depths toform a die of desired width and height made of release material, such asTeflon, through which dough is extruded in a sheet of desireddimensions.

By way of example, the width selector roller 102 shown in FIG. 6 hasfour bars 104, 106, 108, 110, each mounted on the roller drum 103 andmade of a release material such as Teflon. Each bar is notched as shownin FIGS. 6 and 7, the indentations 104a, 106a, 108a being widest at thetop surface of the bar and tapering inwardly, so it is narrowest at thefloor of the indentation. In a preferred embodiment the width of thefirst bar 104 was sixteen inches at the narrowest portion of theindentation, the second bar 106 was twelve inches, the third bar 108 wasten inches and the fourth bar 110 was eight inches. The number of barsand the width of the respective indentations is limited only by thedimensions of the drum 102 and the bars themselves. The thickness roller100 has arranged on the drum 101 a plurality of outwardly extending stepbars arranged to match the several width bar identations in a manner tobe hereafter described. The outwardly extending step bars are arrangedin sets, each set having one or more bars. The number of sets is equalto the number of notched bars on the width selector roller 102. The barsin each set are of identical width but of a different radius, the barsof each set being adapted to nest into a corresponding notched bar but,being of a different radius, each to a different depth. When nested inthe corresponding notched bar, the combination provides an extrusion dieproviding dough sheet thickness which depends upon which of the two ormore outwardly extending step bars has been selected. By way of example,and as shown in FIG. 6, a pair of outwardly extending step bars 112a,112b are provided to nest in the fourth or narrowest notched bar 110;another pair of outwardly extending step bars 114a, 114b are providedfor nesting with the next narrowest notched bar 108. Similarly a stepbar pair 116a, 116b are provided for use with the next notched bar 106,and the widest step bar pair (not shown) are provided for use with thewidest notched bar 104. While only two bars per set are shown, theactual number is limited only by the dimensions of the drum 101 on whichthey are mounted and the bars themselves, provided that each alternatebar be of a constant radius. As best shown in FIG. 9, this expedientprovides a seal with the upper Teflon pad 122, preventing leakage ofdough from the system.

FIGS. 8 and 9 illustrate a practical embodiment of the principlesillustrated in connection with FIGS. 6 and 7. A variable width, variablethickness spreader 124 having a cover plate 126 attached to a spreaderhousing 128 by cover securing means 134, such as bolts, which togetherform a passageway 130, is adapted to connect to conventional screw orother type dough mixing and kneading means, such as by a mounting flange132. An upper, or thickness selector, roller 100 and a lower, or widthselector, roller 102 are mounted on the lower end of the passageway 130,the Teflon bars on each, together forming a die at the egress throughwhich the dough is finally extruded in sheets. The width selector roller102 shown in FIG. 9 has four notched bars 104, 106, 108, 110 mounted onthe width roller drum 103 as previously described in connection withFIG. 6. The drum 103 bears against the lower Teflon pad 120 to effect aseal. However the thickness selector roller 100 is shown as havingsixteen bars or four sets of four bars. Since each alternate bar is ofconstant radius to effect a constant seal with the upper Teflon pad 122,it is seen that this combination affords a choice of two thicknesses foreach of four widths. Thus, in FIG. 9, outwardly extending step bar 112anests in notched bar 110 to form an eight inch die through which doughmay be extruded.

In operation, the desired thickness is selected by manipulation of thecalibrated thickness selector knob 138 which is connected to thethickness roller 100, and the desired width is selected by thecalibrated width selector knob 136 which is connected to the widthselector roller 102. Thereafter roller clamping levers 140a, 104b areactivated to wedge the selected step bar 112a into the matching notch onbar 110, thereby sealing all mating surfaces. The roller clamps may takeany of the forms well known in the art to provide a compressive force onthe roller assemblies to urge the step bar 112a into the matching notchon bar 110, such as a screw type clamp, like in a vise, or a leverassociated with clamp jaws moving along a ramp and in and out of alocked position, or many other expedients well known to those skilled inthe mechanical arts. Thereafter the roller assemblies 100, 102 arepivoted about the axis of the thickness selector roller 100 and clampedtightly in place by another pair of clamps 142a, 142b thereby making aseal of the rollers 100, 102 against the Teflon plates 122, 120 at theegress of the spreader housing 128. The dough is thereafter driventhrough the passageway 130 and through the extrusion die formed by theroller assemblies 100, 102, in a sheet of desired width and thickness.The spreader shown may also contain the degassing feature as illustratedin connection with FIGS. 3 and 4. By utilization of the device asdescribed it is possible to vary the width and thickness of the doughsheet in progressive, finite steps to approximate the dimensions of theend product to be made from the dough being processed. Thus, thespreader can be quickly and simply converted from the processing oftortilla dough to the processing of pizza dough, each of which productshave significantly differing dimensions. The dough extruded from thespreader of the present invention will then approximate the dimensionsof the end product, and intermediate processing for size, whether byhand or machine, is eliminated with resulting economic benefit.

It is also possible to couple the width selector roller 102 with thethickness roller 100 through a gear system like a Geneva Drive or otherintermittent drive so that the corresponding thickness set is alwaysautomatically coupled to each particular width.

.[.We.]. .Iadd.I .Iaddend.claim: .[.1. A sheet spreader for viscousmaterial comprising: an enclosed vessel having an inlet and an egressconnected by an interior passageway for the movement of viscousmaterials therethrough, said passageway being so dimensioned as todiverge generally outwardly in a first plane and to converge generallyinwardly in a plane normal to said first plane as the passagewayprogresses from said inlet toward said egress, said vessel egresscomprising an extrusion die means, means for mounting said vessel sothat the longitudinal axis of said passageway distends downwardly atabout 60° from the horizontal, and in addition, means associated withsaid vessel for removing entrained gases from said viscous materialbeing extruded prior to extrusion through said die means, said degassingmeans extending into said passageway between said inlet and said egressand comprising a plate extending in a biased, touching relationship tothe material moving through said passageway and adapted to move in adirection substantially normal to the flow of material through thepassageway in accordance with the variations in the material density,whereby variable movement of said plate against said material will driveout the gases entrained therein..]. .[.2. A sheet spreader for viscousmaterial comprising: an enclosed vessel having an inlet and an egressconnected by an interior passageway for the movement of viscousmaterials therethrough, said passageway being so dimensioned as todiverge generally outwardly in a first plane and to converge generallyinwardly in a plane normal to said first plane as the passagewayprogresses from said inlet toward said egress, means for mounting saidvessel so that the longitudinal axis of said passageway distendsdownwardly at about 60° from the horizontal, said egress including anextrusion die means comprising an adjustable cooperating roller pair,the first roller of which contains a plurality of bars of differingdimensions on the outer periphery thereof, said bars each having anindentation in the mediate portion thereof, and the second roller ofwhich contains a plurality of bars on the outer periphery thereof, eachof said first and second roller bars being dimensioned so that at leastone of them fixedly and partially nests into the indentation of acorresponding first roller outwardly extending bar in sealingrelationship to form a die through which viscous material may beextruded..].
 3. An extrusion die for viscous material fed thereintounder pressure comprising: an adjustable cooperatng roller pair, thefirst roller of which contains a plurality of bars of differingdimensions on the outer periphery thereof, said bars each having anindentation in the mediate portion thereof, and the second roller ofwhich contains a plurality of bars on the outer periphery thereof, saidfirst and second roller bars being so dimensioned that at least onesecond roller bar fixedly and partially nests into the indentation of acorresponding first roller bar in sealing relationship to form a diethrough which viscous material under pressure may be extruded.
 4. Adevice as set forth in claim 3 wherein the second roller bars comprise aplurality of sets of bars, each set having at least two bars therein,the bars of each set being of constant length as measured in a directionparallel to the axis of rotation of the roller, and of a preselectedheight.
 5. A device as set forth in claim 3 wherein the bars on theouter periphery of the adjustable cooperating roller pair are made of arelease material to which the viscous material to be extruded will notadhere.